[CONTINUUM-2709] Goals/phases aren't required when editing maven build types

git-svn-id: https://svn.apache.org/repos/asf/continuum/trunk@1491080 13f79535-47bb-0310-9956-ffa450edef68
[CONTINUUM-2705] Can't build projects with null builddef fields

git-svn-id: https://svn.apache.org/repos/asf/continuum/trunk@1491081 13f79535-47bb-0310-9956-ffa450edef68